The water cycle

The natural water cycle

Every drop of water on Earth already exists, captured in the ground, oceans, lakes, ice, snow and atmosphere. No new water enters the water cycle. Through the natural water cycle, water is used over and over again.

Did you know? Only 3% of the Earth's water is freshwater and this always remains the same as no new water is added to the water cycle.

What is the water cycle?

Powered by the sun, the cycle from rainfall to evaporation to rainfall is one of the largest physical processes on Earth. Water falls as rain, snow or sleet. It collects in ice, rivers, groundwater and the oceans.

When water evaporates from lakes and oceans, it leaves impurities behind. This means the water cycle naturally cleans the water and is how freshwater is created.

This purification process also occurs when plants transpire (breathe), and water evaporates through their leaves. These natural processes are what keeps the environment healthy.

Water Cycle

How does the water cycle move water around the earth

Human impact on the water cycle

Did you know, humans have impacted the water cycle in many ways? More than 60% of the world’s rivers have been dammed for human use, changing the natural flow of water through the landscape.

While humans need dams to survive, we also have a responsibility to keep our environment healthy.

Delivering water downstream of dams is important for the health of our environment. This process helps to support the fish, plants and animals that live in and beside creeks and rivers. Water released to maintain a healthy river is called an environmental flow.

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WaterNSW acknowledges the traditional custodians of the lands and waters on which we work and pay our respects to all elders past, present and emerging. Learn more